Plural indicator signalling system with selective indicator control

Claim 1

IN A SIGNALLING SYSTEM FOR USE WITH A PLURALITY OF STATIONS, A FIRST AND SECOND SIGNAL; A PLURALITY OF PRIMARY SWITCHES, ONE FOR EACH STATION; MEANS OPERATED BY EACH PRIMARY SWITCH TO ENERGIZE BOTH SIGNALS, A FIRST SWITCH MEANS ASSOCIATED WITH EACH STATION TO RENDER BOTH SIGNALS INOPERATIVE, A SECOND SWITCH MEANS ASSOCIATED WITH EACH STATION TO RENDER ONLY ONE SIGNAL INOPERATIVE; THE MEANS OPERATIED BY EACH PRIMARY SWITCH INCLUDING A PRIMARY RELAY, THE COIL OF WHICH IS IN CIRCUIT WITH THE PRIMARY SWITCH AND THE FIRST SWITCH MEANS, AND THE PRIMARY RELAY SWITCH OF WHICH IS IN CIRCUIT WITH THE TWO SIGNALS; AND THE SECOND SWITCH MEANS COMPRISES A SECOND RELAY HAVING ITS RELAY SWITCH IN CIRCUIT WITH ONE SIGNAL AND ITS COIL SUBJECT TO THE PRIMARY RELAY SWITCH WITH A SWITCH DEVICE IN CIRCUIT WITH THE COIL, WHEREBY CLOSURE OF THE FIRST SWITCH IS NECESSARY TO ENERGIZE THE SIGNALS, AND CLOSURE OF THE SWITCH DEVICE CAN THEN EFFECT ENERGIZATION OF THE SAID SECOND RELAY COIL AND DEENERGIZATION OF ONE SIGNAL; AND WHEREBY OPENING THE FIRST SWITCH MEANS CAN DEENERGIZE BOTH SIGNALS AND THE SECOND RELAY COIL.